The X1950 pro plus vista doesn't make since to me. To me the only reason to go vista is for DX10. the 1950 is only a DX9 card so you just wasted money on the card, OS or both.
Don't go with home basic. If i remember correctly it doesn't have the fancy graphic interface which is basicly the only visual difference between it and XP. It is also highly crippled in what it can do. Get home premium if you want the media center functionality otherwise get biz for the more advanced networking.
I agree with everyone else on the RAM, save yourself 20 bucks and get the G.Skill.
If you are a gamer unfortunatly Creative is basically the only way to go because of their hold on EAX, but if you aren't there are a lot of other brands that make really nice cards for under 100. If you do end up getting a creative card make sure it isn't the extreme audio. It isn't even based on the X-FI chipset. Basically it is a rebranded Audigy 2 SE.